The prize of 10-million-Swedish-krona (US$1.5-million) was divided, one half jointly to Bruce A. Beutler, age 54, at The Scripps Research Institute, La Jolla, California, and Jules A. Hoffmann, age 70, at the French National Centre for Scientific Research (CNRS) Institute of Cell and Molecular Biology in Strasbourg, for their discovery of receptor proteins that can recognize bacteria and other microorganisms and activate innate immunity, and the other half to Ralph M. Steinman, age 68, at Rockefeller University in New York, for his discovery of dendritic cells of the immune system and their unique capacity to activate and regulate adaptive immunity, the later stage of the immune response during which microorganisms are cleared from the body.
There are pathogenic microorganisms in the world (bacteria, virus, fungi and parasites) that continuously threaten our health. Our bodies protect us with powerful defense mechanisms. The first line of defense is innate immunity, which can destroy invading microorganisms and trigger inflammation that contributes to blocking their assault. If microorganisms break through this first line of defense, a second line kicks in: adaptive immunity. Consisting of T cells and B cells, adaptive immunity produces antibodies and killer cells that destroy infected cells. After successfully combating the pathogen, our adaptive immune system maintains an immunologic memory that allows for a more rapid and powerful mobilization of defenses next time the same microorganism attacks.

According to the Nobel committee, these two lines of defense by the immune system have opened up new avenues for the development of prevention and therapy against infections, cancer, and inflammatory diseases [1]:

The discoveries that are awarded the 2011 Nobel Prize have provided novel insights into the activation and regulation of our immune system. They have made possible the development of new methods for preventing and treating disease, for instance with improved vaccines against infections and in attempts to stimulate the immune system to attack tumors. These discoveries also help us understand why the immune system can attack our own tissues, thus providing clues for novel treatment of inflammatory diseases.

NIAID has had the honor of supporting all three awardees. Their elegant work has been — and will continue to be — extraordinary in its impact. It is rare that an investigator makes a discovery so important that it influences virtually every aspect of a scientific discipline. Their discoveries have opened up the possibility of harnessing the body’s own cells and immune processes to prevent infectious diseases, autoimmune disorders, allergic diseases, cancer, and rejection of organ transplants.

Nobel announcement overshadowed by winner’s death

Unknown to the Nobel committee, one of the scientists, Ralph Steinman, died on September 30. This information reached the Nobel Assembly several hours after they had announced the 2011 Nobel Laureates in Physiology or Medicine. The event is unprecedented in the history of the Nobel Prize. Although the Nobel committee cannot issue posthumous awards, the Board of the Nobel Foundation has concluded that the decision to award the Nobel Prize to Ralph Steinman was made in good faith, based on the assumption that the Nobel Laureate was alive [3]. Accordingly, 2011 Nobel Prize in Physiology or Medicine to the late Ralph Steinman remains unchanged.

Ironically, Steinman was being treated for pancreatic cancer with a therapy derived from his original discovery. After being diagnosed with pancreatic cancer four-and-a-half years ago, Steinman launched a life-and-death experiment in the most personal of personalized medicine. He removed a piece of tumor and trained his immune cells to track down any remaining tumor that might escape surgery. This experiment may have given Steinman several years of additional life (less than 4% of people with pancreatic cancer survive 5 years [4]).